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## #76 2011-11-11 23:01:31

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Maiya,

The solution T#20 is 200 √3 + 200 meters = 546.4 meters approximately.

Excellent, bobbym! Keep trying, Maiya!

T#21. If the value of cos A = 1/√2, find the value of tan A.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #77 2011-11-11 23:06:05

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi ganesh;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #78 2011-11-14 23:17:22

Maiya
Member
Registered: 2011-08-11
Posts: 124

hello Ganesh;

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## #79 2011-11-15 00:28:16

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Maiya,

The solution T#21 is correct. Good work!

T#22. A lighthouse was observed from two points in a line with it, but on opposite sides of it. The distance between the points is 120 meters. If the angle of elevation are 30[sup]o[/sup] and 45[sup]o[/sup], find the height of the lighthouse.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #80 2011-11-15 00:50:43

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi ganesh;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #81 2011-11-17 00:02:07

Maiya
Member
Registered: 2011-08-11
Posts: 124

Hello Ganesh;

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## #82 2011-11-17 00:41:17

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Maiya,

The solution T#22 is

meters. Neat job, bobbym!

T#23. Two men are on the opposite sides of a tower. They measure the angles of elevation of the top of the tower as 30° and 45° respectively. If the height of the tower is 150 meters, find the distance between the men.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #83 2011-11-17 00:59:19

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #84 2011-11-24 14:29:31

Stormtangent
Member
Registered: 2011-09-03
Posts: 33

### Re: Trigonometry

Hey guys!  I haven't been online... here's a couple answers

"Have you ever had a dream that you were so sure was real? What if you were unable to wake from that dream? How would you know the difference between the dream world and the real world? "

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## #85 2011-11-24 14:33:43

Stormtangent
Member
Registered: 2011-09-03
Posts: 33

### Re: Trigonometry

"A couple"... lol, my bad.

"Have you ever had a dream that you were so sure was real? What if you were unable to wake from that dream? How would you know the difference between the dream world and the real world? "

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## #86 2011-11-25 00:13:57

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Stormtangent,

bobbym : The solution T#23 is perfect. Excellent!

Stormtangent : The solutions T#21, T#22, and T#23 are perfect. Brilliant!

T#24. From the top of a lighthouse, the angles of depression of two ships floating in a straight line on either sides of the lighthouse are observed as 30[sup]o[/sup] and 45[sup]o[/sup]. If the height of the lighthouse is 200 meters, find the distance between the ships.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #87 2011-11-25 03:50:51

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi ganesh;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #88 2011-11-25 20:38:23

Maiya
Member
Registered: 2011-08-11
Posts: 124

Hello Ganesh;

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## #89 2011-11-26 00:05:43

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Maiya,

bobbym : The solution T#24 is correct. Excellent!

Maiya : The solutions T#23 and T#24 are correct. Excellent!

T#25. If cos A = ½, then tan 2A = ?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #90 2011-11-26 00:08:40

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi ganesh;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #91 2011-11-27 23:56:35

Maiya
Member
Registered: 2011-08-11
Posts: 124

Hello Ganesh;

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## #92 2011-11-28 00:46:46

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Maiya,

The solution T#25 is correct. Stupendous!

T#26. Find the value of

.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #93 2011-11-28 01:59:58

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #94 2011-11-28 23:40:51

Maiya
Member
Registered: 2011-08-11
Posts: 124

### Re: Trigonometry

Hello Ganesh;

Last edited by Maiya (2011-11-28 23:41:40)

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## #95 2011-11-29 00:28:56

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and Maiya,

The solution T#26 is correct, bobbym! Superlative!

T#27. What is the value of sin30sin45sin60 (in degrees)?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #96 2011-11-29 00:52:42

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi ganesh;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #97 2011-12-28 03:27:13

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,030

### Re: Trigonometry

hi ganesh

Last edited by anonimnystefy (2011-12-28 03:27:28)

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #98 2015-03-05 23:48:00

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym and anonimnystefy,

The solution T#27 is correct. Good work!

T#28. Evaluate :

.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #99 2015-03-06 10:52:16

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 108,524

### Re: Trigonometry

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #100 2015-03-06 14:45:54

ganesh
Moderator
Registered: 2005-06-28
Posts: 22,612

### Re: Trigonometry

Hi bobbym,

The solution T#28 is correct. Neat work!

T#29. Evaluate :

.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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